This invention relates to certain 2-[1-(halothienylmethoxyimino)ethyl]-3-hydroxy-5-(tetrahydro-2H-thiopyrany l)-cyclohex-2-en-1-one and salts thereof and to the use of such compounds as herbicides.
U.S. Pat. No. 4,624,696, issued Nov. 25, 1986, discloses compounds having the formula: ##STR1## wherein R.sup.1 is alkyl of 1 to 4 carbon atoms, R.sup.2 is hydrogen or alkoxycarbonyl of 2 to 5 carbon atoms, R.sup.3 is a 5-membered heterocyclic structure which contains 1 to 3 heteroatoms from the group consisting of N, O, and S and may contain 1 or 2 double bonds and 1 or 2 substituents from the group consisting of C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, halogen, trifluoromethyl, C.sub.1 -C.sub.4 -alkoxymethyl, C.sub.1 -C.sub.4 -alkylthiomethyl, vinyl and phenyl, and R.sup.4 is a 5-membered to 7-membered heterocyclic structure which contains one heteroatom or ring member, or two identical or different heteroatoms or ring members, from the group consisting of N, O, S, SO, and SO.sub.2, may contain 1, 2, or 3 double bonds and is unsubstituted or substituted by not more than 2 alkyl or alkoxy groups, each of 1 to 4 carbon atoms, or is a radical of the formula II ##STR2## where X and Y are each N, O, S, SO, or SO.sub.2, and salts of these compounds.
This patent teaches that R.sup.1 is preferably a radical having two or three carbon atoms. The patent describes the compounds as exhibiting herbicidal activity against grasses and safe with respect to a number of enumerated crops.
The patent also teaches that these compounds exhibit herbicidal activity against grasses and are safe with respect to a number of crops.
U.S. Pat. No. 4,596,877 discloses compounds having the formula ##STR3## wherein R.sup.1 is C.sub.1 -C.sub.4 alkyl and R.sup.2 is C.sub.3 -C.sub.5 chloroalkenyl. R.sup.1 is preferably ethyl or propyl.
The compounds are described as being effective to remove grasses while being safe for a number of crops.
My prior U.S. Pat. No. 4,432,786 discloses compounds having the following formulas and their salts: ##STR4## wherein R.sup.1 is hydrogen or lower alkyl;
R.sup.2 and R.sup.3 are independently selected from the group consisting of hydrogen, lower alkyl, aryl having 6 through 10 carbon atoms (preferably phenyl), substituted aryl having 6 through 10 carbon atoms (preferably phenyl) and 1 through 4 substituents (preferably 1 or 2) independently selected from the group consisting of fluoro, chloro, bromo, iodo, or trifluoromethyl;
R.sup.4 is hydrogen or alkoxycarbonyl having 2 through 4 carbon atoms;
R.sup.5 is hydrogen, or an acyl group having 1 through 12 carbon atoms; and
Z is a group having the formula: ##STR5## wherein R.sup.6, R.sup.7, and R.sup.8 are independently selected from the group of hydrogen, halo, nitro, alkyl having 1 through 4 carbon atoms, alkoxy having 1 through 4 carbon atoms, or trifluoromethyl.
In the aforementioned patent, I describe the compounds wherein R.sup.1 is ethyl or propyl and/or Z is a chlorothienyl as preferred. The compounds are described exhibiting excellent grass herbicidal activity.